New Battery advice

I am thinking about a 120 ah drop in lithium from KS energy. I know there have been several threads about lithium but I was wondering if what is claimed is true that these batteries can simply be dropped in to replace lead acid with no other modifications like uprated fuses, B to B etc. I have an Autosleeper Warwick XL which has the Sergeant EC400 system. I would love to hear from anyone who has just simply dropped on in and without modifying anything. It seems the factory fitted battery charger's profile will be fine for the lithium so I am hopeful. It's not that I do not believe what KS Energy claim but Hearing form someone who has actually dome the deed, at out were would boost my confidence.

I'd have to ask why?
Near enough £700 for a battery which, in reality Hasn't that much more capacity than a £120 130Ah lead acid?
Do you have solar?
If not solar installation will be infinitely cheaper and IMHO a far better option in that it'll keep both batteries full all year round....
I know nothing re simply drop in, but would be surprised if that was the case, plenty on here will know much better than me.....

As I understand it lithium are half the weight of lead acid and I would only need one lithium instead of the two lead acid I have. Lithium can be discharged by up to 90% without damage, and they charge faster than lead acid so I am hoping that solar panel Andy occasional drive will keep fully charged. I suppose the bottom line is lithium appear more suited to non EHU use and I will have a little more storage under the bunk.

Do you have solar? On 5 vans now we've had 115Ah LB ,Just one, and 100w solar. Virtually never use EHU, even on sites if extra cost.
Have 2 very happy batteries, VB&LB fully charged all year long. Never been short of power yet.....
Btw on my Warwick Duos the LB was under driver seat?
11 weeks in van this year, btw, poss EHU for 10 nights, never at home...

Yes the usual 80 watt solar. And two 100 Enhanced flooded batteries. I just wonder if lithium would be better.

IanJohnson wrote:I just wonder if lithium would be better.

It depends a bit on what aspect of the installation you need to be better.

If you drop a lithium battery into an existing lead/acid/AGM install, the main area where you will be making a serious compromise is with the maximum rate of charge that you can put back into the battery. What B2B charging does is to drastically improve the maximum charge rate, and to make it more or less independent of the state of charge of the vehicle battery.

If you keep the existing split charge arrangement, firstly you cannot avoid the fact that the vehicle battery will (in effect) get priority when charging from the alternator, and secondly your max charge rate will be 20A at best (and in reality it will probably be a lot less).

And keeping the existing 80W solar panel will make for a very long recharge period for the battery too. In the real world, that panel is only likely to be able to push 4 or 5 Amps into it - which means that it will take days to recharge if it's heavily discharged, if you have to use solar alone.

And... when you're on EHU, the power supply in the EC400 can only recharge it at a max current of 20 Amps.

It puts you in a situation where you have a battery that can (in theory) accept a charge rate of 200 Amps or more - but none of your charging methods can even get to a tenth of that!

However... although it's a compromise, it could be used as a partway installation, which you could augment later with a B2B installation. Though of course that would add a fair bit to the cost, when you account for the labour needed to modify the system...

Ultimately, the decision on which way to go should be guided by the way in which you use the van and what you want to achieve from it. If, for example, you have very high load appliances (microwave, induction hob, etc.) then Lithium Ion batteries will give you the high current delivery and ability to deep discharge without being harmed. If, on the other hand, you have relatively modest loads but want to use the van for extended periods off-grid, it probably makes more sense to increase your solar capacity, and therefore increase the rate at which you can recharge your battery each day without needing EHU.

I think the first question should be is what is your intended use of the van, do you intend to be away and off grid camping when away with no EHU at all or are you using campsites with EHU,

Mostly campsites without EHU are my intentions and staying put for three or four days at a time. Modest power requirements, no microwave or tv and the occasional charge for the phone off of 12 volt USB. Having read this and other forums I think I will pass on lithium for now. I really appreciate the replies I have had which have helped me get to grips with the question

IanJohnson wrote:Mostly campsites without EHU are my intentions and staying put for three or four days at a time. Modest power requirements, no microwave or tv and the occasional charge for the phone off of 12 volt USB. Having read this and other forums I think I will pass on lithium for now. I really appreciate the replies I have had which have helped me get to grips with the question

Are you the person who started the thread ?.

In your case I think that lithiums are over priced when you take into account the extra that may have to be paid out for the correct chargers,  have you looked at the Lead carbon batteries, I have just replaced my lead acid with a 200ah Lead carbon gel battery , these allow a deeper discharge, faster charging and non of the expense of altering the on board chargers, Lead carbon are slightly dearer than acid batteries but not as much as lithium